Hypersonics are generally defined as missiles that can fly more than five times the speed of sound.

ADVERTISEMENT

Gen. John Hyten, commander of U.S. Strategic Command, last week described a hypersonic as a missile that starts out “like a ballistic missile, but then it depresses the trajectory and then flies more like a cruise missile or an airplane. So it goes up into the low reaches of space, and then turns immediately back down and then levels out and flies at a very high level of speed.”

In November, China reportedly conducted two tests of a ballistic missile with a hypersonic glide vehicle that U.S. assessments expect to reach initial operating capability around 2020. The country had already conducted at least seven tests of experimental systems from 2014 to 2016.

Meanwhile, earlier this month, Russian President Vladimir Putin delivered a flashy state of the nation address to tout a slate of new weapons, including a hypersonic missile he claimed was “invincible” against U.S. missile defenses. About a week later, Russia claimed it successfully tested a hypersonic.

At the time of Putin’s announcement, the Pentagon said it was “not surprised” by the report and assured the public that it is “fully prepared” to respond to such a threat.

But in congressional testimony last week, Hyten conceded U.S. missile defense cannot stop hypersonics. He said that the U.S. is instead relying on nuclear deterrence, or the threat of a retaliatory U.S. strike, as its defense against such missiles.

“We don't have any defense that could deny the employment of such a weapon against us, so our response would be our deterrent force, which would be the triad and the nuclear capabilities that we have to respond to such a threat,” Hyten told the Senate Armed Services Committee.

“I believe we need to pursue improved sensor capabilities to be able to track, characterize and attribute the threats, wherever they come from,” he said. “And, right now, we have a challenge with that, with our current on-orbit space architecture and the limited number of radars that we have around the world. In order to see those threats, I believe we need a new space sensor architecture.”

Asked if the U.S. is really falling behind Russia and China on hypersonics, Thomas Karako, director of the Missile Defense Project at the Center for Strategic and International Studies, said flatly: “Yes.”

“And the reason is the U.S. hasn’t been doing anything near the same pace both in terms of developing our own capabilities but also failing to develop sensors and shooters necessary to shoot down theirs,” he continued.

Terrestrial sensors are limited in their ability because of the curvature of the earth, Karako said, but “you can’t hide from a robust constellation of space-based sensors.”

Yet while the last five administrations have identified space-based sensors as a critical need on paper, nothing has come to fruition, he said.

“One of the reasons that we haven’t prioritized the hypersonic threat is we were slow to kind of appreciate not merely the Russia and China problem, but the Russia and China missile problem,” Karako said.

In that regard, he credited the National Defense Strategy and the Nuclear Posture Review, both of which were unveiled by the Trump administration earlier this year, for their renewed focus on a "great power competition" with Russia and China.

“I think we are aware of the capabilities that our adversaries have, and … whether it’s the Nuclear Posture Review, National Defense Strategy, these are all laid out because of the identification of the threats we have,” she said.

Fischer added that there “probably will be” something about hypersonics in her subcommittee’s portion of this year’s annual defense policy bill.

But the Nuclear Posture Review, in particular, has been controversial for its call to develop a sea-launched nuclear cruise missile and a "low yield" warhead for submarine-launched ballistic missiles. Those new capabilities are part of the deterrence that Hyten cited, but critics say the document is poised to fuel an arms race.

“We oppose this approach and will continue to support maintaining an effective nuclear deterrent without wasting taxpayer dollars, inciting a new arms race or risking nuclear conflict,” they said.

In addition to the nuclear review, Pentagon officials have been touting budget proposals that would put more money toward hypersonics and missile defense that they say will help close the gap with Russia and China.

Hyten told the Senate Armed Services Committee that there's $42 million in the fiscal year 2019 budget for the Air Force and the Missile Defense Agency to work on a prototype for space-based sensors.

Air Force Secretary Heather Wilson, meanwhile, told the House Armed Services Committee last week her fiscal 2019 budget includes $258 million for hypersonics.

And Defense Advanced Research Projects Agency (DARPA) Director Steven Walker touted his $256.7 million fiscal 2019 budget for hypersonic missile development the same day as Putin’s press conference. Still, he said, DARPA needs more money for infrastructure to test the missiles, as most of the agency’s testing is done out of one facility.

“The dollars that were allocated in this budget were great, but they were really focused on adding more flight tests and getting some of our offensive capability further down the line into operational prototypes,” he told the Defense Writers Group. “We do need an infusion of dollars in our infrastructure to do hypersonics.”

Inhofe, the senator from Oklahoma, said he’s most worried about the missile defense issue, adding there “appears to be no defense” against hypersonics. To him, the answer is reversing defense budget cuts, which Congress has taken steps to do in a two-year budget deal and a recently passed appropriations bill for fiscal 2018.

“We need to make up the losses that we had during the Obama administration by putting a priority, which we are doing now, on the military,” he said.